<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <div id="hello">
        {{ sj }}
        <p v-if="seen">看见我了</p>
        <p v-if="seen2">看不见我</p>
    </div>


    <script src="https://cdn.jsdelivr.net/npm/vue@2"></script>
    <script>
        var vm = new Vue({
            el: "#hello",
            data: {
                sj: "datou",
                seen: true,
                seen2: false,

            }
        })
    </script>

</body>

</html>